Apparatus for forming and filling bags

ABSTRACT

An apparatus for forming and filling bags of heat sealable packaging material supplied as at least one web has heat sealing jaws for sealing the web when it has been shaped into a tube which are positively coordinated with a brake for the web and a device for forming a loop of the web in such a manner that a loop is formed with the jaws closed and the brake disengaged and is straightened out with the jaws open and the brake engaged when the web is being pulled down under the action of the weight of material filled into the bag.

Elnited States Patent Persson et a1. I Oct. 2., 1973 [54] APPARATUS FORFORMING AND FILLING $238,692 3/1966 MOntuOri 4 53/180 X BAGS 3,457,6957/1969 McCullough 53/182 X 3,471,993 10/1969 Monsecs et a1. 53/180 [75]Inventors: Inge Bertil Persson, Lund; Jim

ga Staffanstorp both of Primary Examiner-Robert I.. Spruill eAttorney-Lester Horwitz ct a1. [73] Assignee: Scan Coin AB, Malmo,Sweden [221 Filed: Sept. 28, 1971 [57] ABSTRACT [21] Appl. No; 184,390An apparatus for forming and filling bags of heat sealable packagingmaterial supplied as at least one web has [52] U S Cl 53/182 heatsealing jaws for sealing the web when it has been [51] hit C1 (/04shaped into a tube which are positively coordinated [58] i 'g 53/i80 82with a brake for the web and a device for forming a 515 3 loop of theweb in such a manner that a loop is formed with the jaws closed and thebrake disengaged and is [56] References Cited straightened out with thejaws open and the brake engaged when the web is being pulled down underthe ac- UNITED STATES PATENTS tion of the weight of material filled intothe bag. 2,606,412 8/1952 Salfisberg 53/180 X 2,636,732 4/1953 Howard53/180 X 5 Claims, 7 Drawing Figures APPARATUS FOR FORMING AND FILLINGBAGS The present invention relates to an apparatus for forming andfilling bags of heat sealable packaging material supplied as at leastone web comprising means for forming a loop of the web, a guide housingwhich is adapted to enclose the web fed thereto in order to shape theweb into a tube, and swingers mounted on either sides of the web ofpackaging material formed in the guide housing and supporting heatsealing jaws for longitudinal sealing of the web, and heat sealing jawsfor transverse sealing of portions of the web projecting from the guidehousing at the lower end thereof.

The apparatus according to the invention is particularly suitable forpackaging small change coins and in that connection the apparatus may bearranged in combination' with a coin counter in order to co-operatetherewith in performing quick and reliable packaging of the coins inbags holding a predetermined number of coins in each bag through anautomatic and continuous cycle of operation. However, the invention isnot limited to this particular type of packaging but may be used alsofor packaging other materials, no matter of what kind they are,including liquid materials.

For the above purpose the invention provides an apparatus of the kindreferred to above characterized in that the heat sealing jaws and theloop forming means as well as a brake for the web of packaging materialare positively coordinated in order to form a loop with the jaws closedand the brake disengaged and straightening out the loop with the jawsopen and the brake engaged when the web is being pulled down under theaction of the weight of the material filled into the bag formed.

An embodiment of the invention provided for packaging coins will bedescribed in greater detail in the following with reference to theaccompanying drawings, in which HO. 1 is a side view, partlydiagrammatic, of the apparatus;

FIG. 2 is a plan view thereof;

FIGS. 3 to S are three views perpendicular to each other of the guidehousing forming part of the apparatus;

FIG. 6 is a lateral view, partly diagrammatic, of the loop forming meansforming part of the apparatus; and

FIG. 7 is a diagram of the electric system of the apparatus.

The apparatus shown in the drawing comprises two shafts 10, on each ofwhich there is freely rotatably journalled a roll 11 of a heat-scalableweb 12, for instance plastic or plastic coated paper. Each roll ispreferably exposed to a slight braking action in order to stop rathersuddenly when the web is no longer withdrawn from the roll. In order toguide the web withdrawn from each roll there is provided a guide roller13 adjacent the roll. A friction brake 14 is engageable with the webopposite to the said guide roller in a manner to be described later. Twoadditional guide rollers 15 and 16 and a guide roller 17 arrangedbetween them, which unlike the other guide rollers is not journalled instationary hearings in the frame of the apparatus but is mounted on aswinger 18, form a loopforming means, as will be described later.Finally there is an additional guide roller 19 for each web 12, saidroller also having stationary bearings and being located immediatelyabove the upper end of a stationary tubular guide housing 20 theconstruction of which is best seen in FIGS. 3 to 5.

The guide housing consists of two bent plates 21 which are provided withinterconnected lugs 22 at their corners, spacers 23 being disposedbetween the lugs, whereby the longitudinal edges of the two plates aremutually spaced in order to define two diametrically opposed slots 24.The two webs 12 which are withdrawn in a manner to be described throughthe guide housing 20 and which are formed into a tube when passingthrough the guide housing will project from the two slots 24 at theirlongitudinal marginal portions in order to be sealed at these portions.For this longitudinal sealing of the two webs there are provided twopairs of mutually co-operating jaws 25A and 25B. These jaws are mountedon a pair of swingers 26 which are suspended by a leaf spring 27 forswinging movement about pivots 28 located at the top. The jaws 25A arepreferably made from silicon rubber or a similar resilientheat-resistant material. On the jaws 258 there is disposed an electricheating wire for impulse heating. The jaws 25A and 25B are disposed inpairs on both sides on the guide housing 20 in order to co-operate inproducing the said longitudinal sealing of the marginal portions of thewebs l2 projecting through the slots 24. For transverse sealing of theweb portions projecting below the guide housing there are disposed onthe swingers 26 four transverse sealing jaws 29A and 298 as well as 30Aand 30B, of which jaws 29A and 30B are of the same construction as thejaws 25A, while the jaws 29B and 30A are of the same construction as thejaws 258. The transverse sealing jaws 29A, 298, which co-operate witheach other, and the transverse sealing jaws 30A and 30B, whichco-operate with each other, are arranged to produce axially spacedtransverse seals, i.e. these seals are spaced in the advancing directionof the two webs. Between the jaws 29B and 30B there is disposed a glowwire 31 for cutting the webs between the transverse seals formed bythese two jaws and the jaws 29A and 308, respectively, co-operatingtherewith. The seals (welds) produced by means of the jaws will bereferred to later in connection with the description of the function ofthe apparatus.

The swingers 26 are held in the spaced apart or open position shown inFlG. l by a U-spring 32 and for actuating the swingers against the biasof the spring there are provided two disks 34, each having an excentriccrank pin 35 on which there is rotatably mounted a roller 36 to bepressed against the associated leaf spring 27. For co-operation withthese crank pins there are also provided leaf springs 37 which projectfrom resilient arms 38 which are fixed to the frame of the apparatus atone end and carry the brakes 14 at the other end. When the cranks 34, 35are rotated the rollers 36 consequently press the swingers 26alternatingly against each other in order to move the swingers togetherand apply the brakes 14 against the guide rollers 13. Thus, the swingerswill be pressed together when the brakes are disengaged while theswingers are moved apart when the brakes are engaged. In order tocontrol the pressure on the jaws there are provided adjustment screws 39for adjusting the bias of the leaf springs 27. At the lower end of oneswinger 26 there are provided a number of pins 40A, while the otherswinger 26 has corresponding apertures 408 for receiving the pins, thefunction of which will become apparent in the following.

The cranks 34, 35 are supported on shafts 41 which are mounted in theframe of the apparatus by means of two bearing plates 42 forming part ofthe frame. The shafts have gear wheels 43 engaging with each other andprovided with excentric crank pins 44. The righthand gear wheel 43 andits associated pin 44 is partly shown in FIG. 6. The previouslymentioned swinger 18 with the guide roller 17 forms one arm of a bellcrank which is pivoted between its ends by means of a shaft 45, whilethe other arm 18A of the bell crank is disposed in the circular path ofmovement of the pin 44. A corresponding arrangement which is shown inFIG. 6 with respect to the right-hand gear wheel 43 of the apparatus isprovided with respect to the left-hand gear wheel 43, which is arrangedto actuate the left-hand lever 18, 18A. The two shafts 45 are journalledin the bearing plates 42 the arm 18 being disposed on the outside of oneplate and the arm 18A being disposed between the two plates. The angularposition of each pin 44 in relation to the angular position of theassociated pin 35 is chosen in such a way that the pin 44 will engagethe arm ll8A in order to swing the bell crank 18, 18A to a positionshown in dot and dash lines in FIG. 6 for the left-hand bell crank,while the rollers 35 keep the swingers 26 pressed together and thebrakes 14 are consequently disengaged for withdrawing the webs 12. Thismeans that through the downward movement, thus produced, of the guideroller 17 from the position shown in solid lines in FIG. 6 to theposition shown in dot and dash lines there is produced a loop of eachweb 12 between the guide rollers 15, 16 and 17. After these loops havebeen formed and the engagement of the pins 44 with the arms 18A hasceased, the bell cranks will remain in the position shown in dot anddash lines and the webs 12 are braked again by engagement of the brakes14 by means of the rollers 36.

Swinging of the bell cranks 18, 18A from the position shown in dot anddash lines in FIG. 6 to the position shown in solid lines is broughtabout by withdrawing the webs 12 with the brakes 14 engaged in a mannerto be described later, and in order to determine the position shown insolid lines'in FIG. 6 there is provided a stop member 46 which isvertically adjustable. It is provided as a nut on a screw spindle 47rotatably mounted in the frame and having an operating knob 48, the stopmember 46 being held non-rotatably but vertically displaceably in theframe so that by turning the spindle 47 it is possible to producevertical movement of the stop member 46.

In order to operate the gear wheels 43 there is provided a transmissionwith gears 49, 50, 51 and 52, the last-mentioned gear being driven by anelctric motor not shown. All these gears are non-rotatably mounted onshafts which in turn are journalled between the two bearing plates 42 inthe frame.

The function of the apparatus will now be described starting from theposition shown in solid lines in the drawings, in which case it isassumed that the webs 12 have been withdrawn through the guide housing20 and are in the position shown in FIG. 3. During the operation of theapparatus the cranks 34, 35 are rotated synchronously with each otherand with the gear wheels 43 by means of the driving motor of theapparatus, the rollers 36 moving the swingers 26 towards each other sothat the jaws are pressed against each other. Immediately afterwards therollers 35 disengage the brakes 14. While the jaws are kept pressedagainst each other the marginal portions of the two webs projectingthrough the slots 24 are heat-sealed by means of the jaws 25A, 25B byproducing welds 53 and the webs are heatsealed at the portions thereofprojecting from the lower end of the guide housing by means of the jaws29A, 29B and 30A and 3013 by producing welds 54 and 55. At the same timethe webs are cut between the welds 54 and 55 at 56 by means of the glowwire 31. It is assumed that in a previous operation of the apparatusthere have been produced welds S3, overlapping being provided betweenthe welds 53 and 53'. After these welds have been produced the two websare consequently united into a bag closed at the sides and at thebottom, said bag being located in the guide housing 20. Through impulsesfrom the packaging apparatus to a filling machine disposed above it andsupplying the material to be packaged, e.g. a coin counter for supplyinga predetermined number of coins, the predetermined amount is nowsupplied through an outlet tube opening in the guide housing 20 betweenthe webs 12 but not shown, to the bag open at the top. After the jawshave been pressed together the driving motor is allowed to continue itsoperation, the levers 18, 18A being swung from the position shown insolid lines through the position shown in dot and dash lines, while thejaws are still pressed against each other. Since the brakes 14 aredisengaged during this operation and the webs drawn into the guidehousing 20 are immobilized by means of the jaws, the webs 12 areconsequently withdrawn from the rolls 11 in order to form the loopsbetween the guide rollers 16 and 17 as described above. The motor isthen stopped and is immobilized with the jaws closed in order to producewelds of sufficient strength. It is restarted after a suitable timeinterval sufficient for welding and cooling, the rollers 36 allowing theswingers 26 to be moved apart under the action of the spring 32. Theserollers are now pressed against the leaf springs 37 for engaging thebrakes 14 immediately before the jaws are moved apart. Due to the factthat the jaws are moved apart from below and in a direction upwards,material which may stick to the jaws is successively torn loose from thejaws. With the brakes 14 engaged the material filled into the bag willwithdraw the two webs due to its weight after the jaws have been movedapart, the filled bag sinking down through and out of the guide housing20. Possibly, the levers 18, 18A may be spring biassed towards theposition shown in solid lines in FIG. 6. The previously formed web loopsproduce the requisite web length for the withdrawal at the same time asthe levers 18, 18A are swung back to the position shown in solid lines.The downward movement of the filled bag is limited by the stop member 46in a manner described previously. After this operation the welds 53previously formed are thus in the position corresponding the welds 53 inFIG. 3. During the next welding operation the filled bag will be sealedat the top by means of the weld 55 and will be cut off from the portionof the two webs located in the guide housing at 56 so that a package ofthe type appearing from FIG. 3 and designated 57 in that figure isobtained. In order that air enclosed in the package may escape from thepackage it is punctured by means of the pins 40A at 58 when the swingers26A, 26B are moved together. This puncture may also funtion as a tearnotch for opening the bag.

The electric system for operating the described apparatus, which isshown in FIG. 7, comprises the driving motor of the apparatus which isshown at 60 and which can be connected to the electric mains 61 by aswitch 62 which is normally in the shown position at a contact a but isswitched to the other position at a contact b when the swingers 26 arein the pressed-together position, and two switches 63 and 64, of whichthe switch 63 is normally in a closed position but is in an openposition when the swingers 26 are in the separated position. Theswitches 62 and 63 are consequently shown in the position, which theyoccupy when the swingers are moved apart. An additional switch 64normally opened and connected in parallel with the switch 63 is adaptedto be actuated by a sensing means in the outlet for the filled bags inorder to be kept in a closed position as long as a bag is located in oris passing through the outlet. Finally, the circuit of the motor 60comprises a relay contact 65A of a relay 65, connected in parallel withthe switches 62, 63, 64. This relay contact is closed when the relay isenergized. The wiring diagram also comprises an electric motor 66 whichcan be connected to the mains by the switch 62 being moved to theposition at the contact b and this motor is part of the filling machinewhich is provided in connection with the apparatus according to theinvention in order to supply the material to be packaged inpredetermined quantities. Thus, the motor may form part of a machine forcounting coins and supplying an amount of coins at a predeterminedvalue.

To the mains 61 there is also connected the primary of a transformer 67the secondary of which provides low-voltage to the control circuits ofthe related motor driving circuits. These control circuits comprise therelay 65 which can be connected to the transformer 67 by a push-buttonswitch 68 connected in parallel with a normally closed relay contact 69Aof a relay 69 and a normally opened switch 70 which is mounted in thefilling machine. When the switch 68 or alternatively the relay contact69A and the switch 70 are closed a current pulse will be supplied to therelay 65 from the transformer through rectifiers 71 and a condenser 72.The relay will hold the contact 65A in the closed position and anadditional contact 658 associated with the realy and normally engaging acontact a, in the position at a contact b. The contact 658 providesself-holding of the relay 65 by means of a condenser 73 which haspreviously been charged from the transformer 67 through one ofrectifiers 71 when the contact 65B was in the position a so that therelay 65 remains energized for a short time after the supply of currentthrough the condenser 72 has ceased. Assuming that the swingers 26 areinitially in a separated position this means that the motor 60 will beenergized through the contact 65A for a sufficiently long time to permitthe swingers to move so far that the switch 63 will be closed and themotor 60 then will be energized through the switch 62 and the switch 63.The relay 65 cannot obtain a new impulse through the condenser 72 untilthere has been an interruption at the switch 68 and this has been closedagain.

When the swingers driven by the motor 60 againsc the bias of the spring32 reach the completely pressedtogether position they actuate the switch62 which is reset to its contact b, which means that the motor 60 of theapparatus stops, while the motor 66 of the filling machine starts. Atthe same time as the switch 62 is actuated a normally opened switch 74is however also actuated, said switch 74 supplying a current pulse to arelay 77 through rectifiers 75 and a condenser 76. This relay is part ofa stabilized time circuit for controlling the current supply to theelectrically heated jaws 258, I

298 and 30A, the heaters of which are collectively marked at 78, and tothe glow wire 31. The relay 77 comprises a contact 77A which is normallyat a contact a, a condenser 78 which is connected in parallel to a Zenerdiode 80 being charged. When the relay 77 is en ergized the contact 77Awill be engaged with a contact b in order that the condenser 79 maysupply selfholding current to the relay 77 through variable resistors 81and 82. The relay 77 consequently remains activated for a certain timewhich is determined by the setting of the two resistors 81 and 82, oneof which provides rough setting while the other one provides finesetting of the desired activation time. A thermistor 83 compensates forheat accumulated in the jaws so that the time set is shortened atincreased temperature. When the relay 77 is activated a normally openedcontact 77B is also engaged and this contact, which is protected bymeans of a thyristor 85 closes the circuit through the heaters 78 andthe glow wire 31, and a pulling magnet 86 in the filling machine bymeans of which the said machine is activated in order to supply thepredetermined portion of the material to be packaged; its motor 66 isalready in operation. The filling machine in the manner describedpreviously now feeds the predetermined portion of the material to bepackaged, into the bag which has been prepared in the packagingapparatus as described above. The contact 77B also closes the circuit toa bridge rectifier 87 which supplies current to a condenser 88,connected in parallel with the relay 69 which in this part of thefunction will be energized from the rectifier 85 by the closing of thecontact 77B. This means that the contact 69A will be opened at the sametime as the welding operation begins. When the predetermined portion hasbeen supplied by the feeding machine the switch 70 is closed by means ofa sensing member in said machine but since the contact 69A is opened themotor 60 cannot be started (except by means of the push-button switch68, which is not normally to be actuated during the automatic operationof the apparatus). The time circuit of which the relay 77 is a part willinterrupt the current supply to the relay 77 after the predeterminedtime interval with consequent opening of the contact 77A. As a resultthe current supply to the magnet 86, the heaters 78, the glow wire 31and the bridge rectifier 85 ceases but since the relay 69 thereuponremains energized by current supplied from the condenser 88 the contact69A will remain in the opened position for a predetermined time intervalduring which the welds formed are cooled while the jaws remain pressedtogether. When this predetermined time interval has also elapsed therelay 69 becomes deenergized so that the contact 69A will be closed andprovided that the filling operation is then finished so that the switch70 is closed, a new current pulse will be supplied for energizing therelay 65 and repeating the operation described.

Thus, it appears that the circuit shown in FIG. 7 keeps the apparatusaccording to the invention in operation after the push-button switch 68has been closed at the beginning in order to provide a starting pulse,and controls the operation in such a way that the previ ously describedoperational cycle for forming and welding the webs and filling the bagswill be performed automatically and will be repeated over and overagain.

Obviously, however, other circuits than those described may be used forcontrolling the apparatus, and such circuits has to be matched to thetype of filling machine combined with the packaging apparatus.

What we claim is:

1. Apparatus for forming and filling bags of heat sealable packagingmaterial supplied as at least one web comprising means for forming aloop of the web; a guide housing enclosing the web over a substantiallyvertical length thereof in order to shape the web into a tube andforming side openings to expose marginal portions of the length of theweb enclosed by the guide housing; swingers mounted on either sides ofthe web of packaging material when shaped into a tube in the guidehousing; first heat sealing jaws for longitudinal sealing of the web atthe exposed marginal portions thereof; second heat sealing jaws fortransverse sealing of portions of the web projecting from the guidehousing at the lower end thereof; said first and second heat sealingmeans being supported by the swingers; driving means for pivoting theswingers to move the sealing means supported thereby between opened andclosed positions; a brake for the web of packaging material; operatingmeans for engaging and disengaging the brake; means operativelyinterconnecting the swinger driving means, the brake operating means,and the loop forming means to lengthen the loop formed by the loopforming means when the jaws are being closed with the brake disengagedand to allow shortening of the loop when the jaws are being opened withthe brake engaged by withdrawal of the web due to the gravity ofmaterial filled into the bag formed, the filling bag being dischargedfrom the guide housing at the lower end thereof.

2. Apparatus as claimed in claim 1, further comprising means for cuttingthe web of packaging material, the transverse sealing jaws beingprovided partly above and partly below the cutting means.

3. Apparatus as claimed in claim 1, further comprising rotatableeccentric means and driving means therefor for actuating the heatsealing jaws to a closed position.

4. Apparatus as claimed in claim 3, wherein the excentric means areadapted to actuate also the brake for the web in order to keep the brakeengaged when the heat sealing jaws are open.

5. Apparatus as claimed in claim 4, further comprising a time circuitfor controlling the driving means of said excentric means in order tostop the movement of the excentric means during a predetermined timeinterval with the heat sealing jaws closed and for energizing the heatsealing jaws during a predetermined short time interval which fallsduring the first-mentioned time interval.

1. Apparatus for forming and filling bags of heat sealable packagingmaterial supplied as at least one web comprising means for forming aloop of the web; a guide housing enclosing the web over a substantiallyvertical length thereof in order to shape the web into a tube andforming side openings to expose marginal portions of the length of theweb enclosed by the guide housing; swingers mounted on either sides ofthe web of packaging material when shaped into a tube in the guidehousing; first heat sealing jaws for longitudinal sealing of the web atthe exposed marginal portions thereof; second heat sealing jaws fortransverse sealing of portions of the web projecting from the guidehousing at the lower end thereof; said first and second heat sealingmeans being supported by the swingers; driving means for pivoting theswingers to move the sealing means supported thereby between opened andclosed positions; a brake for the web of packaging material; operatingmeans for engaging and disengaging the brake; means operativelyinterconnecting the swinger driving means, the brake operating means,and the loop forming means to lengthen the loop formed by the loopforming means when the jaws are being closed with the brake disengagedand to allow shortening of the loop when the jaws are being opened withthe brake engaged by withdrawal of the web due to the gravity ofmaterial filled into the bag formed, the filling bag being dischargedfrom the guiDe housing at the lower end thereof.
 2. Apparatus as claimedin claim 1, further comprising means for cutting the web of packagingmaterial, the transverse sealing jaws being provided partly above andpartly below the cutting means.
 3. Apparatus as claimed in claim 1,further comprising rotatable eccentric means and driving means thereforfor actuating the heat sealing jaws to a closed position.
 4. Apparatusas claimed in claim 3, wherein the excentric means are adapted toactuate also the brake for the web in order to keep the brake engagedwhen the heat sealing jaws are open.
 5. Apparatus as claimed in claim 4,further comprising a time circuit for controlling the driving means ofsaid excentric means in order to stop the movement of the excentricmeans during a predetermined time interval with the heat sealing jawsclosed and for energizing the heat sealing jaws during a predeterminedshort time interval which falls during the first-mentioned timeinterval.